Heat dissipation device

ABSTRACT

A heat dissipation device includes a heat sink and a heat pipe. The heat sink includes a first fin assembly and two second fin assemblies located on two opposite sides of the first fin assembly respectively. The heat pipe includes an evaporator section, a first condenser section and a second condenser section extending from two opposite ends of the evaporator section in the same directions, and a third condenser section extending from a free end of the second condenser section towards a free end of the first condenser section. The third condenser section extends through the first fin assembly. The first condenser section interconnects one of the second fin assemblies to the first fin assembly. The second condenser section interconnects the other second fin assembly to the first fin assembly.

BACKGROUND

1. Technical Field

The disclosure relates to heat dissipation, and particularly to a heat dissipation device for dissipating heat generated by an electronic component.

2. Description of Related Art

Electronic components operating at high speed generate excessive heat which must be displaced efficiently to ensure normal operation. Typically, a heat dissipation device attached to the electronic component provides such heat dissipation.

A conventional heat dissipation device includes a metal base for contacting and absorbing heat from the electronic component, a straight heat pipe with an evaporator section thereof attached to the base, and a heat sink including a plurality fins attached to a condenser section of the heat pipe. By this configuration, firstly, the heat generated by the electronic component is conducted to the base, and then transferred to the heat sink through the heat pipe, and finally is dissipated to ambient by the fins.

For enhancing a heat dissipation effectiveness of the heat dissipation device, a heat dissipation area of the heat sink is greatly increased. However, a heat contacting area between the heat pipe and the heat sink, due to the restriction by the configurations of the heat pipe and the heat sink, cannot be increased. Thus, most of heat generated by the electronic component and absorbed by the evaporator section of the heat pipe can not be transferred to the heat sink timely, and therefore the heat dissipation effectiveness of the heat dissipation device is limited.

It is thus desirable to provide a heat dissipation device which can overcome the described limitations.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric, assembled view of a heat dissipation device according to an exemplary embodiment.

FIG. 2 is an exploded view of the heat dissipation device of FIG. 1.

FIG. 3 is similar to FIG. 2, but viewed from a bottom aspect.

DETAILED DESCRIPTION

Reference will now be made to the drawing figures to describe the present heat dissipation device in detail.

FIGS. 1-2 illustrate a heat dissipation device for dissipating heat generated by an electronic component (not shown) which is mounted on a printed circuit board (not shown). The heat dissipation device includes two heat pipes 10, a heat sink 20, a clip 30, and a heat-absorbing block 40. The clip 30 spans across the heat sink 20 to secure the heat dissipation device on the printed circuit board. Heat generated by the electronic component is absorbed by the heat-absorbing block 40, transferred to the heat sink 20 via the heat pipes 10 and dissipated into air through the heat sink 20.

The heat-absorbing block 40 has a planar bottom surface 41 (FIG. 3) contacting with the electronic component and a top surface 42 for supporting the heat sink 20 and the heat pipes 10 thereon. The top surface 42 includes a flat middle portion 421 and two slant portions 422 protruding upwardly and slantways from left and right sides of the flat middle portion 421, respectively. Thus, the flat middle portion 421 is recessed between the slant portions 422.

Each of the heat pipes 10 includes an evaporator section 14, a first condenser section 11 and a second condenser section 12 extending perpendicularly from two opposite ends of the evaporator section 14 in the same direction, and a third condenser section 13 extending from a free end of the second condenser section 12 towards a free end of the first condenser section 11. The first condenser section 11 is parallel to the second condenser section 12, and has a length slightly shorter than the second condenser section 12. The third condenser section 13 is parallel to the evaporator section 14, and has a length slightly longer than the evaporator section 14. The first condenser section 11, the evaporator section 14, the second condenser section 12 and the third condenser section 13 cooperatively form a rectangle with an opening 16 being formed between a free end of the third condenser section 13 and the free end of the first condenser section 11.

The heat sink 20 in whole has a substantially rectangular configuration. The heat sink 20 includes a first fin assembly 21, and two second fin assemblies 23 arranged at two opposite sides of the first fin assembly 21, respectively.

The first fin assembly 21 includes a plurality of parallel first fins 210 arranged side by side and a plurality of parallel heat dissipation vanes 212 arranged side by side and located on two opposite sides (i.e., front and rear sides) of the first fins 210. Each of the heat dissipation vanes 212 has a size smaller than the first fin 210. In this embodiment, each of the first fins 210 and the heat dissipation vanes 212 extends along a left-to-right direction of the heat sink 20. The first fins 210 are located on a middle portion of the first fin assembly 21. The heat dissipation vanes 212 on the front side of the first fin assembly 21 are grouped into two spaced units on a left end and a right end of the heat sink 20, respectively, thus to form two horny portions 213 on the front side of the first fin assembly 21. A first receiving room 216 is defined between the two horny portions 213 on the front side of the first fin assembly 21. Similarly, the heat dissipation vanes 212 on the rear side of the first fin assembly 21 are grouped into two units on the left end and the right end of the heat sink 20, respectively, thus to form another two horny portions 213 on the rear side of the first fin assembly 21, and a second receiving room 216 is defined between the another two horny portions 213 on the rear side of the first fin assembly 21. Accordingly, a top plan view of the first fin assembly 21 is generally H-shaped.

Two through holes 217 are defined in the left end and the right end of the first fin assembly 21, respectively. Each of the through holes 217 extends through the first fins 210 and the heat dissipation vanes 212 along a front-to-rear direction. Each of the through holes 217 receives the third condenser section 13 of a corresponding heat pipe 10 therein. A groove 218 is defined in a middle portion of a bottom side of the first fins 210. The groove 218 has an upper portion having a width substantially the same as the flat middle portion 421 of the heat-absorbing block 40, and slightly larger than a sum of the widths of the evaporator sections 14 of the heat pipes 10. A distance between each of the through holes 217 and the groove 218 substantially equals to the distance between the third condenser section 13 and the evaporator section 14 of each heat pipe 10, i.e., the length of the second condenser section 12. When assembled, the block 40 couples to the bottom side of the first fins 210, and thus the groove 218 and the flat middle portion 421 of the heat-absorbing block 40 cooperatively form a receiving space having a depth equal to a diameter of the evaporator section 14 of the heat pipe 10; thus, the evaporator sections 14 of the heat pipes 10 can be sandwiched closely between the bottom side of the first fins 210 and the flat middle portion 421 of the heat-absorbing block 40.

The second fin assemblies 23 have substantially the same configuration to each other, and are received in the first and the second receiving rooms 216 of the first fin assembly 21, respectively. Each of the second fin assemblies 23 includes a base 230, a plurality of second fins 231 extending perpendicularly and upwardly from a top surface of the base 230 and a plurality of second fins 231 extending perpendicularly and downwardly from a bottom surface of the base 230. The second fins 231 are parallel to each other and arranged side by side. Each of the second fins 231 extends along the front-to-rear direction of the heat sink 20, being perpendicular to the first fins 210.

The base 230 includes an elongated plated portion 232 and a pair of aliform portions 233 extending upwardly and slantways from two opposite ends (i.e., left and right ends) of the plated portion 232, respectively, to render the base 230 to have a substantially V-shaped configuration. A pair of slots 234 concaved from inner sides of the aliform portions 233, respectively, which face the first fin assembly 21. One slot 234 receives the second condenser section 12 of one of the heat pipes 10, and the other slot 234 receives the first condenser section 11 of the other heat pipe 10. A trough 236 is defined under the plated portion 232 of the base 230 to prevent the heat pipes 10 from interfering with the second fin assemblies 23. The trough 236 communicates with bottom ends of the slots 234, and has a shape substantially equal to the groove 218 of the first fin assembly 21. The trough 236 and the groove 218 cooperatively form a receiving channel under the bottom side of the heat sink 20 for receiving the evaporator sections 14 of the heat pipes 10 side by side.

During assembly of the heat sink 20, referring to FIG. 3, the first fin assembly 21 is pre-assembled with the heat pipes 10 extending therethrough. The third condenser sections 13 of the heat pipes 10 insert into the through holes 217 formed at the left side and the right side of the first fin assembly 21, respectively. The evaporator sections 14 received in the groove 218 are in thermal engagement with the bottom side of the first fin assembly 21. The second condenser sections 12 extend outwardly from the third condenser sections 13 to the evaporator sections 14 and the first condenser sections 11 extend outwardly from the evaporator sections 14 towards the free end of the third condenser sections 13 are in thermal engagement with outmost first fins 210 at the front and the rear sides of the first fin assembly 21, respectively. Then, the second fin assemblies 23 are received in the first and the second receiving rooms 216 of the first fin assembly 21, respectively, with the first condenser sections 11 and the second condenser sections 12 of the heat pipes 10 being received in the slots 234 of the base 230 correspondingly. The first condenser sections 11 and the second condenser sections 12 of the heat pipes 10 embedded into the slots 234 of the second fin assemblies 23 are connected with the second fin assemblies 23 by soldering. Accordingly, the heat sink 20 is assembled.

The heat-absorbing block 40 is installed on the electronic component with the bottom surface 41 thereof attaching to the electronic component; the heat sink 20 with the heat pipes 30 is mounted on the heat-absorbing block 40; and the heat sink 20 is mounted on the printed circuit board via the clip 30. The bottom side of the first fin assembly 21 and the second fin assemblies 23 and the evaporator sections 14 of the heat pipes 10 are in thermal contact with the top surface 42 of the heat-absorbing block 40.

During operation of the heat dissipation device, the heat-absorbing block 40 absorbs heat from the electronic component; the heat is spread on the first fins 210, the heat dissipation vanes 212 and the second fins 231 via the heat pipes 10; and finally the heat is dissipated to ambient air via the first fins 210, the heat dissipation vanes 212 and the second fins 231. Since each of the heat pipes 10 includes the first condenser section 11, the second condenser section 12 and the third condenser section 13 which are fully in thermal contact with the first fin assembly 21 and the second fin assemblies 23, a large heat contacting area between the heat pipes 10 and the heat sink 20 is provided. The heat pipes 10 have excellent heat transfer performance due to their low thermal resistance, and therefore heat generated by the electronic component is absorbed by the evaporator sections 14 of the heat pipes 10 and is quickly and effectively transferred to different portions of the heat sink 20 far from the electronic component, via the large heat contacting area between the condenser sections 11, 12, 13 of the heat pipe 10 and the heat sink 20, respectively. Accordingly, the heat dissipation efficiency of the heat dissipation device is improved.

It is to be understood, however, that even though numerous characteristics and advantages of the disclosure have been set forth in the foregoing description, together with details of the structure and function of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. 

1. A heat dissipation device comprising: a heat sink comprising a first fin assembly and two second fin assemblies located on two opposite sides of the first fin assembly respectively; and a heat pipe comprising an evaporator section, a first condenser section and a second condenser section extending from two opposite ends of the evaporator section in the same directions, and a third condenser section extending from a free end of the second condenser section towards a free end of the first condenser section, the third condenser section extending through the first fin assembly, the first condenser section interconnecting one of the second fin assemblies to the first fin assembly, and the second condenser section interconnecting the other second fin assembly to the first fin assembly.
 2. The heat dissipation device as described in claim 1, wherein the first condenser section, the evaporator section, the second condenser section and the third condenser section cooperatively from a rectangle, with an opening being formed between a free end of the third condenser section and the free end of the first condenser section.
 3. The heat dissipation device as described in claim 1, wherein the first fin assembly defines a through hole for the third condenser section of the heat pipe extending therethrough, the evaporator section thermally contacting with a bottom side of the first fin assembly.
 4. The heat dissipation device as described in claim 3, wherein each of the second assemblies defines a slot facing the first fin assembly, and the first condenser section and the second condenser section of the heat pipe are received in the slots of the second assemblies, respectively.
 5. The heat dissipation device as described in claim 4, wherein the first fin assembly comprises a plurality of first fins and a plurality of heat dissipation vanes each having a smaller size than each of the first fins, the heat dissipation vanes arranged on four corners of the first fin assembly to form four horny portions on the four corners correspondingly, two receiving rooms being defined in the two opposite side of the first fin assembly respectively, each of the receiving rooms being defined between two corresponding horny portions, the second assemblies being received in the receiving rooms respectively.
 6. The heat dissipation device as described in claim 1, further comprising another heat pipe having the same configuration with the heat pipe, the first fin assembly defining another through hole for a third condenser section of the another heat pipe extending therethrough, an evaporator section of the another heat pipe thermally contacting with the bottom side of the first fin assembly and be arranged side by side to the evaporator diction of the heat pipe.
 7. The heat dissipation device as described in claim 6, wherein each of the second assemblies defines a pair of slots facing the first fin assembly, the first condenser section of the heat pipe and a second condenser section of the another heat pipe are received in the pair of slots of one of the second assemblies, respectively, and the second condenser section of the heat pipe and a first condenser section of the another heat pipe are received in the pair of slots of the other one of the second assemblies, respectively.
 8. The heat dissipation device as described in claim 7, wherein each of the second assemblies comprises a base and a plurality of second fins extending outwardly from the base, the base comprising a plated portion and a pair of aliform portions extending upwardly and slantways from two opposite ends of the plated portion to make the base have a substantially V-shaped configuration, the slots being defined in one surface of the aliform portions of the base facing the first fin assembly.
 9. The heat dissipation device as described in claim 7, wherein the slots defined in each of the second fin assemblies are V-shaped.
 10. A heat dissipation device comprising: a heat sink comprising a first fin assembly and two second fin assemblies located on two opposite sides of the first fin assembly respectively; and a heat pipe comprising an evaporator section and three condenser sections, the evaporator section and the three condenser sections cooperatively form a rectangle with an opening being formed between free ends of the heat pipe, one of the condenser sections interconnecting one of the second fin assemblies to the first fin assembly, one of the condenser sections interconnecting the other second fin assembly to the first fin assembly, and the one of the condenser sections extending through the first fin assembly.
 11. The heat dissipation device as described in claim 10, further comprising another heat pipe having the same configuration with the heat pipe, the first fin assembly defining two through holes for the two condenser sections of the heat pipes extending therethrough, the evaporator sections of the heat pipes being arranged side by side and thermally contacting with bottom side of the first fin assembly.
 12. The heat dissipation device as described in claim 11, wherein each of the second fin assemblies defines a pair of slots on one side facing the first fin assembly, the other four condenser sections of the heat pipes interconnecting the second fin assemblies and the first fin assembly being received in the slots of the second fin assemblies correspondingly.
 13. The heat dissipation device as described in claim 12, wherein the slots of each second fin assembly receive two condenser sections of different heat pipes therein. 